Het nummer is duizend.

Because nummer is a het-word in Dutch. Dutch nouns are either de-words or het-words, and you have to learn which article goes with each noun.

• singular: het nummer
• plural: de nummers

So in this sentence, het is simply the correct definite article for nummer.

Here, nummer means number.

So Het nummer is duizend means that the number is one thousand.

A useful note: nummer can also mean other things in Dutch depending on context, such as:

• a song/track: een mooi nummer
• a number in a list: nummer drie
• a phone number: telefoonnummer

In this sentence, it is being used in the basic numerical sense.

Yes, sometimes, but they are not always exactly the same.

• getal = a number in the mathematical sense
• nummer = number as a label, identifier, or general everyday word

If you are talking about mathematics, Het getal is duizend may sound more precise.
If you are just using everyday language, Het nummer is duizend can still be understandable depending on context.

So a learner should know that getal is often the more specifically mathematical word.

This is the normal Dutch word order for a simple statement:

• Het nummer = subject
• is = verb
• duizend = complement

Dutch main clauses usually put the finite verb in the second position, so this follows the standard pattern:

subject + verb + rest

That is why Het nummer is duizend is the expected basic order.

Because Dutch usually does not use een when simply naming the number itself.

So:

• duizend = one thousand

Using een duizend would usually sound unnatural if you are just identifying the number. Dutch normally says:

• duizend
• honderd
• tien

Very occasionally, één duizend could be used for emphasis or contrast, but that is not the normal default form.

Duizend is pronounced approximately like DUY-zunt, but the first vowel is a real Dutch sound and does not match English exactly.

A rough guide:

• dui has the Dutch ui sound, which is difficult for English speakers
• stress is on the first syllable: DUI-zend
• the final d is often pronounced softly, and the second syllable can sound like zunt or zənd depending on accent

A more phonetic version is:

• /ˈdœy.zənt/

The hardest part for most learners is the ui sound.

In careful speech, het is pronounced roughly like het with a short e.

But in normal spoken Dutch, het is very often reduced and sounds more like ut.

So you may hear:

• careful: het
• common spoken form: ut

That reduction is very normal in everyday Dutch.

Yes. You can write:

• Het nummer is duizend.
• Het nummer is 1000.

Both are possible. Writing the numeral is very common, especially in practical contexts such as lists, labels, forms, or technical writing.

If you write larger numbers in Dutch, remember that Dutch uses a comma for decimals and often a period or space for thousands, depending on style.

Yes, very closely. Is is the third-person singular form of zijn (to be).

Compare:

• English: The number is one thousand.
• Dutch: Het nummer is duizend.

So in this sentence, is functions just like English is.

Because Dutch does not capitalize number words in the middle of a sentence unless there is some special reason.

So:

• Het nummer is duizend. ✅
• Het nummer is Duizend. ❌

Dutch capitalization rules are similar to English here: ordinary nouns and number words are not capitalized unless they begin the sentence or are part of a name.

If you make nummer plural, the article changes from het to de:

• singular: het nummer
• plural: de nummers

Example:

• De nummers zijn duizend en één.

This is a very common pattern in Dutch: many het-words become de in the plural.